https://leetcode-cn.com/problems/two-sum/submissions/

    1. class Solution(object):
    2.     def twoSum(self, nums, target):
    3.         """
    4.         :type nums: List[int]
    5.         :type target: int
    6.         :rtype: List[int]
    7.         """
    8.         hashmap = dict()
    9.         for i, num in enumerate(nums):
    10.             if(target-num in hashmap):
    11.                 return [hashmap[target-num], i]
    12.             hashmap[num] = i